What power supply for diagnostics?

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DanHolman
Joined: Sun 10 Jul, 2016 10:43
Posts: 45

  Z3 roadster 1.9

What power supply for diagnostics?

Post by DanHolman »

Hi All,

What level of power supply unit are people using for diagnostics? I'm looking on eBay; 0-30V with 0-10 amps seems to be the most common range. Are these Suitable? What level of amps do the diagnostics draw? I'm thinking of using progman to reset the ABS unit. There is a YouTube vid for reference.

Thanks
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Robert T
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Joined: Mon 12 Jun, 2006 10:35
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  Z3 roadster 1.9
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Re: What power supply for diagnostics?

Post by Robert T »

What sort of diagnostics? I run INPA on a laptop running on its internal battery, with the car on ignition position II running on its battery. This works just fine, which is good as I have no power in the garage. Or are you trying to power components away from the car?

Cheers R.

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colb
Joined: Sat 05 May, 2012 22:46
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  Z3 roadster 1.8 TU
Location: Newport South Wales UK

Re: What power supply for diagnostics?

Post by colb »

You don't need a power supply to run diagnostic code readers, they get their power from the diagnostic sockets they are plugged into.
If you use a laptop with software diagnostics on it then the laptop mains cable can be plugged in to power the laptop if needed or just rely on the laptop battery.
Colb
1999 BMW 1.8 Z3
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DanHolman
Joined: Sun 10 Jul, 2016 10:43
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  Z3 roadster 1.9

Re: What power supply for diagnostics?

Post by DanHolman »

As mentioned, I will be using progman and maybe DIS/TIS, part of the inpa package.
When using these diagnostic tools- especially when re programing it seems that a very steady external 13V supply must be used, as stated in the BMW manuals that have come with the software.
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pingu
Joined: Fri 30 Apr, 2004 16:01
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  M roadster S50

Re: What power supply for diagnostics?

Post by pingu »

DanHolman wrote:As mentioned, I will be using progman and maybe DIS/TIS, part of the inpa package.
When using these diagnostic tools- especially when re programing it seems that a very steady external 13V supply must be used, as stated in the BMW manuals that have come with the software.
Can you send us a link to the software? I've never heard of any software needing to be powered to use it. In fact, it sounds dangerous to the car's electronics for you to be "pushing" power into the ECU.
Pingu
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stevov
Joined: Sun 21 Dec, 2014 15:56
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  Z3 roadster 2.0
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Re: What power supply for diagnostics?

Post by stevov »

The only power supply that is possibly required when using diagnostics is a 12 volt battery charger connected to the car battery to maintain system voltage. Extended periods of diagnostics can lower battery voltage especially when running system actuator and function tests.
DanHolman
Joined: Sun 10 Jul, 2016 10:43
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  Z3 roadster 1.9

Re: What power supply for diagnostics?

Post by DanHolman »

Its not Voltage that fries electronics its amps. The car will take voltage up to around 14-15v it seems (not that you would ever do that). When using progman for example it draws amps. If this draw discharges the battery enough (below the specified 13V) while coding is in progress, It causes problems and stops running. I think actually they say 13v but its probably more like 12.6-7 V the un cranked Voltage of a battery in good condition at the top of its charge. Also, It seems that programing/reprograming needs a very steady voltage which is achieved through an external power supply. I don't know about you but I'm listening to that advice.

Maybe I'll upload screenshots of the manual if possible? Check out power supply automotive diagnostics on YouTube this is not BMW specific.

Has anyone using Progman, Inpa... got/can recommend one? BMW specify 0-30v 0-40 amps but these are expensive 0-30v 0-10 amps are affordable...

I'm trying not to waist money on one that won't do the job, Know what I mean?

I want to do this right. As my first girlfriend used to say; don't rush in like a bull in a china shop!
gookah
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Joined: Thu 07 Aug, 2008 09:51
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  Z3 roadster 2.8

Re: What power supply for diagnostics?

Post by gookah »

I have never needed a power supply when doing diagnostics or coding with INPA and NCSexpert for the ABS module. Current draw is very low, and it usually doesnt take very long.
Battery will last hours on diagnostics provided everything else is not being used. turn off heater fans, lights etc etc first.

Most diagnostic tests can be done with the engine running, and coding takes seconds.... :puzzle:

Not sure you will get a recommendation for a power supply, because it seems no one else has ever needed to use one... even my local BMW indy doesn't use one.
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pingu
Joined: Fri 30 Apr, 2004 16:01
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  M roadster S50

Re: What power supply for diagnostics?

Post by pingu »

DanHolman wrote:Its not Voltage that fries electronics its amps. The car will take voltage up to around 14-15v it seems (not that you would ever do that). When using progman for example it draws amps. If this draw discharges the battery enough (below the specified 13V) while coding is in progress, It causes problems and stops running. I think actually they say 13v but its probably more like 12.6-7 V the un cranked Voltage of a battery in good condition at the top of its charge. Also, It seems that programing/reprograming needs a very steady voltage which is achieved through an external power supply. I don't know about you but I'm listening to that advice.

Maybe I'll upload screenshots of the manual if possible? Check out power supply automotive diagnostics on YouTube this is not BMW specific.

Has anyone using Progman, Inpa... got/can recommend one? BMW specify 0-30v 0-40 amps but these are expensive 0-30v 0-10 amps are affordable...

I'm trying not to waist money on one that won't do the job, Know what I mean?

I want to do this right. As my first girlfriend used to say; don't rush in like a bull in a china shop!
Now I think I understand what you are trying to do!!!

I think most of us thought you were trying to download data (like in INPA). You are actually trying to recode the ECU by uploading data, and the car will have the ignition on, but will not be charging and the voltage will be dropping all the time. You want the car to maintain a stable voltage of around 13v all the time the car is being uploaded to.

Am I correct?

If you are going to use a charger, you need the voltage and power (or voltage and current) specifications required by the software. Then you need to compare those against the chargers available. If the specification of the voltage "ripples" under all loads up to 40A is tight, you will need a very expensive charger. No matter what charger you use, it will not be a flat DC that is produced - it will have "ripples". For this reason, I would use a bank of batteries. Batteries are DC and the voltage will only drop slightly as current is drawn as long as the jump leads you use are of good quality. The voltage from a charger will be "fluttering" all the time, even when there is no load.

I would fully charge the car battery and use a bank of at least two other car batteries. I'd use good quality jump leads (not cheap £10 ones). I'd use a voltmeter to ensure the voltage stayed within the specified range at all times.
Pingu
gookah
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  Z3 roadster 2.8

Re: What power supply for diagnostics?

Post by gookah »

and I would just chance it....
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Z3 2.8 Progress Journal (Mine)
Z3 1.9 Sport Progress Journal (Wifey's)

I have an element of 'M-styling' on my car, If that's a good enough reason for the manufacturers to adorn a 320 with the M badge, then its certainly a good enough reason for me..
DanHolman
Joined: Sun 10 Jul, 2016 10:43
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  Z3 roadster 1.9

Re: What power supply for diagnostics?

Post by DanHolman »

You've got it Pingu !!! That is exactly the idea I'm trying to get across; stable voltage when recoding/data transfer. This is the requirement BMW issue in their manual (will try to screen shot ). There is even a photo of the power supply they use.

After reading the replies though, it seems possible that working to BMW standard practice may not be necessary here. No one else seems to be bothered doing this. I suppose when people take in their car for time consuming recoding/diag. etc. they hook up an external source to cancel even the slightest chance that the customers battery is effected/drained or worse the coding is interrupted. The customers battery may be in bad shape to begin with etc. time is money so they hook up an external.

It is best practice it seems, but it may be overkill if you know your battery is in good nick from a recent charge. Good. That has saved me £50 on a power supply.

Many thanks all
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